Backhoes are frequently utilized during the excavation of residential, small business and other types of work sites. As known in the art, backhoes typically are equipped with a hydraulically operated front end loader and a consisting typically of a bucket mounted on an arm that is mounted on an articulated boom. Four hydraulic actuators, or rams, provide for side-to-side pivoting of the boom, raising and lowering the boom, flexing and extending the arm in relation to the boom, and actuation of the bucket. As known in the art, it is frequently necessary to remove large tree trunks from the work site. This action requires the use of opposable claws, rather than the bucket typically found on the backhoe. Heretofore, an end effector mountable on the distal end of the arm required an additional hydraulic ram in order to provide actuation of the claws for the purpose of grasping the logs.
Typical of the art regarding end effectors and claw mechanisms are the following U.S. Patents: U.S. Pat. No. 5,544,435 issued to Somero on Aug. 13, 1996, discloses a brush rake for attachment to an arm equipped with a bucket. The Somero device is used in conjunction with the bucket and requires an additional hydraulic ram. U.S. Pat. No. 5,150,936 issued to Avery on Sep. 29, 1992, discloses a grapple assembly for attachment to a workhead. Avery's grapple is designed to be received by a shear that is actuated by two hydraulic rams. Finally, U.S. Pat. No. 5,328,223 issued to Maggio on Jul. 12, 1994, discloses an end grapple for use on loader tractors in nurseries to load and unload trees and shrubs onto and off of trucks. Maggio's pivotal fingers require the use of an hydraulic ram (64) in addition to the hydraulic ram (14) utilized to pivot the workhead with relation to the distal end of the arm. Other known patents include the following:
______________________________________ Inventor U.S. Pat. No. Date Issued ______________________________________ Wooley, jr. 5,033,785 Jul. 23, 1991 De Gier et al. 5,062,227 Nov. 5, 1991 Jacobsen et al. 5,172,951 Dec. 22, 1992 Lin 5,192,104 Mar. 9, 1993 Rogers, Sr. et al. 5,209,536 May 11, 1993 White 5,244,338 Sep. 14, 1993 Jacobsen et al. 5,328,224 Jul. 12, 1994 Gagne et al. 5,486,085 Jan. 23, 1996 Christensen 5,641,190 Jun. 24, 1997 ______________________________________
What is missing from the art is a claw grapple that can be readily interchanged with a typical bucket on a backhoe arm without requiring an additional hydraulic ram to actuate the claw mechanism.
Accordingly, it is an object of the present invention to provide a grapple having opposable claws that is adapted to be carried by the distal end of the arm on a backhoe.
A further object of the present invention is to provide a grapple claw in which the opposing claw members are actuated by the single hydraulic ram that actuates a typical backhoe bucket.
Still another object of the present invention is to provide a grapple claw that is readily interchangeable with the bucket of a state of the art backhoe.
Other objects and advantages over the prior art will become apparent to those skilled in the art upon reading the detailed description together with the drawings as described as follows.